/Engine/Source/Runtime/Core/Public/Math/UnrealMathUtility.h
Returns true if there is an intersection between the segment specified by StartPoint and Endpoint, and the Triangle defined by A, B and C. If there is an intersection, the point is placed in out_IntersectionPoint
true if intersection occurred
static bool SegmentTriangleIntersection ( const FVector & StartPoint, const FVector & EndPoint, const FVector & A, const FVector & B, const FVector & C, FVector & OutIntersectPoint, FVector & OutTriangleNormal )